Pacification has been generally welcomed in favelas, where residents have seen a drop in crime.

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Prof Anthony Pereira, professor of Brazil Studies at Kings College London, says the pacification programme is "largely positive".

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Allowing East Germans to watch American soap operas on West German television, for example, seems to have acted as a form of pacification that actually reduced people's interest in politics.

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It is like a new city has been born within Rio de Janeiro as a result of the pacification initiatives and companies are figuring out how to best attract the opportunities there.

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But there are more than 600 favelas in the city, and critics say the pacification programme only benefits areas near richer neighbourhoods popular with tourists or Olympic and World Cup venues, our correspondent adds.

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However, Prof Neri says the biggest problem of the pacification scheme is how the wider Rio economy can offer jobs to the large number of youths in the favelas now getting a better education.

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The next stage was to implant a UPP, or Police Pacification Unit, a team of police officers specially trained in community relations to establish state presence and allow the conditions to begin the legalization of the favela.

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With Rio set to hold a number games in the 2014 World Cup, and host the Summer Olympics in 2016, Prof Pereira says these events are definitely the force behind the pacification programme, and it should "on balance" be welcomed.

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That's since changed, with the pacification of dozens of Rio's "favela" hillside slums, the discovery of offshore oil deposits that have flooded the city with petrodollars and Rio's role as host for the 2014 soccer World Cup and the 2016 Olympic Games.

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